Treatment of tar for the manufacture of pitch and recovery of light oils.



. No. 827,113. PATENTED JULY 31, 190 W. OPPENHEIMER. TREATMENT OF TAR FOR THE MANUFACTURE OF PITCH AN'D RECOVERY OF LIGHT OILS.

*PPLIOATION FILED 111M521. 190a.

1 v UNITED STATES PATENT OFFICE.

I WILLIAM OPPENHEIMER, F EWELL, ENGLAND. TREATMENT OF TARFOR THE, MANUFACTURE OF PITCH AND RECOVERYIOF LIGHT oust T To a ZZ wham it may concern: l

Be it known that LWILLIAM OPPENHEIMER,

. a subject'of the King of Great Britain and Ireland, residing .at Ewell, Surrey, England,

(whose post-office address is Ewell Castle,

4 Ewell, Surrey,) have invented a certain new and useful Improvement in the Treatment of of June, 1903 in Germany on the th dayv August, '1903,') of whichuthe following is a Tar for the Manufacture of Pitch and Recovcry of Light Oils, (for which I have applied for a patent in Great Britain on. the 5t day of July, 1903; in Austria on the lstday of August, 1903; in Hungary on the 3d day of August, {1903 in Bel ium on the 7th dayof August, 1903, and in rance on the 7 th day of in the latte-rare evaporated 'and added to the 7 gas, while the heavier hydrocarbons, together with any other substances whichmay be contained in themineral oil, yield thetar. This 4 'tar always contains water, which can'only' be separated with great diiliculty, owing to its specific gravity being almost the same as that of the tar.

; zation of this kind of tar, however, the water contained in it is a great obstacle. During its distillation violent and dangerous commotion takes'place. Moreover the water condensed on the cooler walls o1 coining in contact with the boiling oil. In

consequence of these difficulties the usual method ofutilizing this kind of tar consists-in converting it into, pitch by heating the tar in open receptacles and allowing the .volatile products to escape.

v The-present invention has for its object to recover the volatile oils of the tar. as well as the pitch' For this purpose the tar is first relieved of its water by chemical means be fore subjecting it to distillation in' a retort.

The removal of the water is preferably efl'ected by means of caustic lim'e-(CaOlor;

burntgypsum, (CaSO which materials are known to absorb water and to combine chemically with the same, while forming calcium hydrate, Ca(OH) or calcium sulfate,

' oaso,.+2H,o. I I For carrying out this process an averagesample of the tar to be worked up (which Specification of Letters Patent. Application filed Augusti'l, 19013. Serial'No.1'71,013,

F or-the rational industrial utili the retort flows back and causes unpleasant phenomena upon forms a thin and practically non-viscous li'quid) iscarefully tested as regards the uantity of water contained in it, after whic the necessary quantity of caustic lime or burnt gypsum is ascertained lay-calculation and careymixed with the tar. The latter is then allowed-to stand until the calcium hydrate or'the hydrated calcium sulfateformed by this rocedure has settled at the bottomfafter W ich the tar, stillforming a thin liq uid, is drawn off vfatefas mentioned above, the compound of' lime thus produced settles at the bottom of the receptacle in a physically dry state. This separation or precipitation takes place very easily and smoothly, because water-gas tar,

unlike ordinary coal-tar, is a very thin liquid.

The treatment of the tar with the lime or burnt v gyp nary mixmg vessel or tank rovided with an agitator, and for the distil ation of the. tar which has been drawn off after the treatment he used. Theaccompanylng drawing shows the genan ordinary still and cooling apparatus may eral arrangement of apparatus-which maybe used for performing my invention.

a represents a m1x1ng-tank containing a ro- I tary agitator b and provided with a draw-oil cock 0, from which the dehydrated tar may be drawn oil into an intermediate tank d or directly into the still e. The vapors formed in the latter are'conducted through aipecoil mounted in a tank g, filled with col Water, and are thereby condensed.

Incase' caustic lime is used for dehydration the slaked lime thereby obtained may of course be treated for the recovery of caustic sum may take place in an ord i-.

lime in a suitable kiln, and the oily matter adh ering to it may be recovered at the same time.

deprived of water yields a much more brilliant and more valuable quality of pitch than that which can be obtained by simply heating the water-gas tar in an openv receptacle and allowing the'yolatile products to escape; secondly,-the valuable volatile constituents. of tar, which With-the usual method of working are allowed toescape as awast'e roduct, may be. recovered by known met ods as The advanta cs resulting from my process are as follows: irst, the tar which has been ICO products of the fractional distillation of the specially-prepared tar. M

It is not new to treat tar with lime, such a rocess having been described, for instance, in the specification of British Patent No.

' 1,910 of 1858, which relates to the treatment of ordinary coal-tar by mixing it with sufficient lime to produce a perfectly dry paste which will not liquefy at the temperature used in the distillation of tar, the said dry paste being then heated for obtaining gase ous and liquid products. My invention is limited to the treatment of water-gas tar, which alone produces the results described above.

What I claim is 1. The rocess for the utilization of watergas tar, w iich consists in first deprivingithe tarofi water by mixing it with a calcareous 20 compound adapted to absorb water by forming a chemical combination" with the same,

then allowing the m xture to stand, mechan ically separating the calcareous matter from the tar and subjectin the tar to distillation, substantially as descri ed and for the purpose specified. I

2. The process for the utilization of watergas, tar, which consists in first relievin the tar of Water by treatment withcaustic lime, then mechanically separating the tar from the lime, and subjecting it to distillation, substantially as described and for the purpose specified. i

In Witness whereof I have hereunto signed Witnesses.

WILLIAM OPPENHEIMER. Witnesses:

H. D. JAMESON, C. P. LInDoN.

' my name in the presence of two subscribing 5 

